Centrifugal pump and compressor.



R. F. HALLIWELL.

CENTRIFUGAL PUMP AND COMPRESSOR.

APPLICATION FILED SEPT- IB i916.

1,284,662. Patented NOV. 12, 1012s.

Inventor" R egin. a? Haulweu.

Mis'umorneg UNITED STATES PATENT oFFIoE.

REGINALD F. HALLIWELL, OF RUGBY, ENGLAND, ASSIGNOR T0 GENERAL ELEUTRIU COMPANY, A CORPORATION OF NEW YORK.

CENTRIFUG'AL PUMP AND COMPIEESSOR.

Specification of Letters Patent.

Patented Nov. 12, 1918.

To all whom it may concern:

Be it known that I, REGINALD F. HALLI- WELL, :1 subject of the King of Great Britain, residing at Rugby, in the county of WVarwickshire, England, have invented certain new and useful Improvements in Centrifugal Pumps and Compressors, of which the following is a specification.

The present invention relates to centrifugal pumps and compressors, such as are used, for example, to supply water or other liquid under pressure to a conduit, or to Supply air or gas under pressure to a conuit.

In the case of a liquid pump, the invention relates particularly to cases wherein the amount of liquid required varies from time to time. It has been found that when little or no liquid is bein withdrawn from the discharge conduit, the liquid in the pump casing, due to the friction, gets heated up very. quickly, which may cause considerable trouble.

In the case of air or gas compressors, a condition of operation occurs at light load which is known as brbakdown of pressure.

-When this condition is reached what are commonly termed pulsations occur, and if this is not checked the compressor may be damaged or the output may drop to zero and remain there.

The object of the present invention is to rovide an improved regulating mechanism or a puirp or compressor which, in the one case, will prevent heating of the liquid in I the pump, and in the other will prevent the occurrence of pulsations.

To this end I provide a bypass pipe which connects the discharge side of the pump or compressor'to the inlet side thereof, or to any other point, so that the bypass pipe may act as a waste pipe for wasting fluid from the dischar e side of the pump or compressor, and in tliis pipe Larrange a valve which is under the joint control of the delivery pressure of\ the pump or compressor, and the pressure of the elastic fluid which is being admitted to the turbine or other.

prime mover utilized in driving the pump or compressor. In case the prime mover is a turbine it may be either a single stage or a multiple stage machine. As is well understood, the pressure at. the inlet of a turbine or at an stage there is indicative of the load an the elastic uid pressure just referred to may accordingly be taken from any point in the turbine where the pressure varies with the load.

In the present instance I have shown my invention as applied to a centrifugal pump used for supplying water to a conduit.

In the drawing, Figure 1 is a diagrammatic view of a pumping system embodying my invention, and Fig. 2 is a sectional elevation of a bypass valve used therein.

Referrin to the drawing, 3 indicates a steam turblne which may be either a single stage or a multiple stage machine. It is supplied with steam from a suitable source through a pipe 4, the steam exhaustintg through the outlet 5. Mounted on the sha of the turbine is a centrifugal pump 6 drawing water from a tank 7 through the suction pipe 8, and delivering it to the main 9. The steam supply to the turbine is governed by a suitable regulator or controlling valve mechanism 10 which is controlled by the pressure in the delivery main 9, the same being connected to it by the pipe 10". The bypass valve 11, shown enlarged .in section in Fig. 2, is situated in the delivery main and comprises a piston 12 connected to a valve 13. The under side of this valve is exposed to the pressure of the feed water,- while the upper side of the piston 12 is subjected to the pressure of the steam supplied to the turbine 3, its casing being connected to the steam chest by a pipe 14. The outlet from the valve is connected to the feed tank by a pipe 15. ZIn the present instance the pipe 14 is shown as being connected to the steam chest of the turbine 3 between the turbine and the regulator 10, but it will be understood that my invention is not limited to this exact arrangement it being only necessary that the pipe 14 be connected with the turbine at a point be ond the regulator 10 as regards the flow o steam so that the pressure in such pipe varies with the load on the turbine.

The operation is as follows:

While considerable quantities of water, gas or air are being withdrawn from the main 9; the prime mover and pump will be running at their normal speeds and the steam in the steam chest or one of the intermediate stages of the prime mover will be of sufiicient pressure to cause the bypass valve the water, air or gas in ,the main.

\Vhen smaller quantities of fluid or gas are Withdrawn from the main, however, the pressure in the delivery main increases and the supply of steam to the prime mover is automatically diminished. The pressure, therefore, in the steam chest, or one of the intermediate stages is diminished, and with it the pressure acting on the u per side of piston 12 to hold the bypass valve 13 on its seat, while the pressure tending to raise it is increased. By suitably proportioning the areas upon which these pressures act, the bypass valve may be arranged to open at any desired pressure in the main.

When this opens, a certain quantity of fluid or gas from the pump or compressor will flow through the bypass and be returned either to the source from which the pump or compressor derives its supply or to waste, thereby insuring a constant minimum amount of fluid or gas passing through the pump or compressor, even if no fiuid or gas is being Wil'lnlrawn from the delivery main.

In the case of the pump, this insures that steam xvi ll not be formed in the pump casing due to the heat generated from fluid friction, and in the case of compressors it insures that the compressor will always be operating at a load slightly in excess of the breakdown point of the same.

In accordance with the provisions of the patent statutes, I have described the princi ple of operation of m invention, together with the apparatus which I now consider to represent the best embodiment thereof; but

I desire to have it understood that the ap paratus shown is only illustrative, and that the invention can he carried out by other means.

What 1' claim as new and desire to secure by Lettc utcnt of the United States, is, l. The combination. with a centrifugal In 'hinc and a prime mover, for driving it,

valve mechanism frn regulating the adof ilEtStla': fluid to the prime mover, a waste pipe connected to the discharge side of the machine, a valve therein, and means controlled jointly by the pressure of the mo tive fluid at a point beyond said valve mechanism as regards the flow of elastic fluid and the deliver pressure of said centrifugal machine for regulating said valve.

The con'ibination with a centrifugal machine and a prime mover for driving it, of a valve mechanism for regulating the admission of chi ".ic fluid to the prime mover, a waste pipe l; .mccted to the discharge side of the machine, a valve therein, and a mow able abutment connected to the valve, one

side of which is subjected to the pressure of the motive fluid at a pint beyond said valve mechanism as regar tic fluid and the other to the delivery pressure of the machine.

3. The combination machine and a prime mover utilizing elastic fluid for driving it, of a valve mechanism responsive to the delivery pressure of the centrifugal machine for regulating admission of elastic fluid to the prime mover, a waste pipe connected to the discharge side of the machine, and a valve in said waste pipe controlled jointly by the pressure of the elastic fluid at a point" beyond said valve mecha nism as regards the flow of elastic fluid and with a centrifugal s the flow of elasthe delivery pressure of the centrifugal' mafluid for driving it, of a valve mechanism responsive to the delivery pressure of the centrifugal machine for regulating the admission of elastic fluid to the prime mover, a. waste pipe connected to the discharge side of the machine, a valve therein, a movable abutment connected to the valve, a conduit connectin one side of the abutment to the delivery side of the machine, and a conduit connecting the other side to an elastic fluid passage of the prime mover at a point beyond said valve mechanism as regards the direction of flow of elastic fluid.

5. The combination of an elastic-fluid turbine,'a pump driven thereby: a supply tank, a conduit connecting the delivery side of the ump to the supply tank, a valve in the condilit, and means controlled by the delivery pressure of the pump and the pressure at a point in the elastic-fluid turbine for regu.

lating said valve whereby the same will be opened at light or no load.

6. The combination of an elastic-fluid turbine, a pump driven thereby, a supply tank, a conduit connecting the delivery side of the pump to the supply tank, a valve in the conduit, means controlled by the delivery pressure of the pump and the pressure at a,point in the elastic-fluid turbine for regulating said valve, and a re ulating mechanism for the turbine controlled by the delivery pressure of the pump.

In witness whereof, I have hereunto set my hand this thirtieth day of August, 1916.

REGINALD F. HALLIWEI JL. 

